Hotbars+ v2.0 Prerelease 2

This is the second official prerelease build of Hotbars+ v2. It is still missing some features from v1.x currently (such as load and save failure detection), however I hope to bring them back as I get closer to the final version.

What's new from v2.0-pre1:

• Fixes bug where trying to view the list of cached hotbars in 1.14.x/1.15.x crashed the game
• Fancy new icons for the hooks for 1.14/1.15, 1.16, and 1.17/1.18
• Code cleanup
• Overhauls how the mod hooks into the vanilla system
• 1.19.x support